Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
THE MILLED DRILL
The fixture allows drilling machine, flat and profile milling lumber, cutting of grooves and ridges in the edges of boards for rallying, sampling thorns and eyes corner joints joinery...
FROG IN THE KITCHEN SINK
Like it or protect the drain hole of the kitchen sink all sorts of motorolafree — it's a no-no and clogged. "Punch" garbage Prabhu can help magni pump“frog”, how pumped up air...